The invention relates generally to the fuel management of an internal combustion engine. More particularly, the invention relates to an engine equipped with a fuel metering system and including an arbitrarily settable fuel injection mechanism as well as an automatically adjusted air throttle in the induction tube. The fuel supply system to which the invention specifically relates includes an air flow rate meter which is displaced by the air flowing through the induction tube and which controls the position of the air throttle on the basis of information related to the actual fuel flow to the engine. In the known fuel supply system to which this invention relates, the displacement of the air flow throttle is so slow that it is unable to follow rapid displacements of the fuel control member in the fuel metering system so that a sudden displacement of the control member may cause temporary excessive enrichment of the fuel-air mixture.